Device for bending coils



E Jan. 27, 1959 R. H. GREENE DEVICE Foa BENDING cons 2 Sheets-Sheet 1 med Jan. so, .1956 Y INVENToR.. RAV/vano H. GREENE BY my 44 TTOPNS R. H. GREENE DEVICE FOR BENDING COILS Jan. 27, l1959 Filed Jan. so. 195e 2 Sheets-Sheet 2 INVENTOR.

#Amo/va H. GAff/vf my l A Trop/Veys E DEVICE FOR BENDING CGILS 4 Raymond H. Greene, Detroit, Mich., assignor to Calu- `met `& Hecla, Inc., Chicago, Ill., a corporation of Michigan Application January 30, 1956, Serial No. 562,121

S Claims. (Cl. 153-40) This invention relates to method and apparatus for -bending a length of stock into a coil.`

sitions at opposite ends of the slot and in such positionsl of the pin the fixture is rotated 180 to bend the stock around the adjacent member.

Another object of the invention is to provide apparatus of the above general description which is particularly adapted to form tubing or stock having an outer coil and an inner coil telescoped within the outer coil from one continuous length of stock. `In the past, it has been necessary to separately form `the inner and outer coils and to weld or otherwise ends of the inner and outer coils.`

Still `another object of the invention is 'to provide a method for bending a length of stock into a coil which greatly facilitates and simplies the operation.

Other objects of the invention will become apparent as the following description proceeds especially when taken in conjunction with the accompanying Adrawings wherein:

Figure 1 is a plan view of apparatus embodying the invention.

join `together the United' statesmen-'1o Figure 2 is a sectional view taken along the line 2-2 j on Figure 1. j t

Figure 3 is a plan view showing the apparatus in another position.

Figure 4 is a sectional view taken along the line 4-4 on Figure 1.

Figure 5 is an enlarged plan view of a portion of Figure 4.

Figure 6 is a sectional view taken along the line 6-6 on Figure 5.

Figure 7 illustrates a modification,

Figure 8 is a sectional View along the line 8-8 on Figure 7.

Referring now more particularly to the drawings and especially to Figures 1-6, the apparatus includes a king pin 10 fixed to the circular plate-like table 12 and extending upwardly at right angles. An elongated fixture 14 in the form of a hat plate has a slot 16 therein extending in the direction of length of the tixture. The width of the slot is approximately equal to or slightly4 greater than the diameter of pin 10 and the pin is received in the slot. The fixture can slide on the pin from vone end of the slot to the other and is rotatable on the pin in any position of the pin in the slot.

. Located at opposite ends of the slot. are a pair` of of sheet metal, for example, andY extend upwardly from the xture 14 at right angles thereto. The radius plates are in the form of hollow half cylinders and the centers of the half cylinder radius plates coincide with the axis of pin 10 when it is located at either end of the slot. Thus, as seeen in Figure 1, the axis of the half cylinder radius plate 19 coincides with the axis of pin 10.

Referring to Figure 2, it will be seen that the king pin 10 projects beneath the table 12 and an arm 20 has one end formed with a sleeve portion 22 which` is rotatably supported on the pin. The arm extends laterally from the king pin and upwardly beyond the table. A guide block support 26 is carried by the upper end of arm 20. The guide block 28 has a portion 30 supported in the recess 30" in the top surface of support 26. Portion 30 has ribs 31 on opposite sides slida'ble in grooves 32 in the side walls of .recess 30' and compression springs 33 between the rear wall 34 of the recess `and portion 30 urge block 28 outwardly. The front end of the j permit it to be rotated relative to and independently of p the fixture.

A disk-shaped cam 38 is mounted on the support 26 for rotation on the pin 40 which is carried by the support. An arm 42 projects outwardly from the cam to rotate the latter and thereby urge theguide block 28 against the bottom coil.

The fixture 14 is shown supporting a coil of stock S which is in the form of one single continuous length of tubular stock. The inner coil S1 has its ends received in the hollow inner surfaces of the radius: plates. This inner coil may be formed in any desired manner on any conventional bending apparatus and then slipped into position within and between the radius plates. The bottom free `extremity of the inner coil is then extended at a slight angle, as shownat 43, to the longitudinal axis of the iixture laterally` outwardly so that it may be bent around the outer sides of the radius plates of the lixture 14 to form the outer coil S2. t

With the fixture iu the` position shown in Figures 1 and 2, the guide block 28 bears against the lowermost section of stock S2 which is unbent and extends laterally outwardly from the fixture as shown at 44. In the operation of the fixture, the stock 44 to be bent is always at the bottom of the series of coils and the coils are built up by the continued bending operation. The outer coil is shown partially completed in Figures l and 2. In order to form another bend in the outer coil, the handle 42 is grasped and forced in a clockwise direction withrespect to the pin 40 to urge the block 28 against the lowermost coil and'also cause the fixture to rotate about the axis of king pin'10. The fixture will be rotated and at the end of this operation will as sume the position shown in solid lines in Figure 3. Thereafter the arm 20 is returned to its starting position, shown in dotted lines in Figure 3. Following that, the fixture 14 is slid on the king pin to the dotted` line position of Figure 3 in preparation for the bending of another loop of the coil in the same manner. y

The coil may be built up in a stepwise fashion, b continuingwith the 180 rotation of the lixture at one end of the slot and subsequent 180 rotation thereof follow` ing movement of the iixture to the other end of the slot relative to the pin.

The purpose of the guide block 28 is primarily to keep Ythe length of stock 44.being bent from bulging in the `region of `the radius plate. In order to hold the length andere being bent against bulgingat the opposite side of the bend, the stop "46 is'provided supported on the table for rotation by a pivot pin 48. The stop 46 is held in operative position, as shown in Figure l by a pin 50 pivoted on plates. i

As pointed out above, one important use of this apparatus is .in forming stock having inner and outer coils S1 and S2 from a continuous length of stock. The inner `coil may be formed in any suitable manner and the outer coil formed as described above. It will be understood that the inner coil S1 might be formed on a nxture such as the one described by merely substituting radius plates having a smaller radius of curvature. When thus forming the inner coil S1, it would be built up on the outer surfaces of the radius plates and the radius plates would not have to be hollow, that is the inner surfaces would not have to be concave. The purpose of concave radius plates is to provide a support for an inner coil while the outer coil of a continuous length of stock is being formed.

The apparatus is thus adapted to form a coil of stock on the outer surfaces of the radius plates whether or not an inner coil is present and supported on the fixture. The hollow or concave inner surfaces of the radius plates are for the purpose of supporting such an inner coil.

Figures 7 and 8 show a modification. The king pin is received for sliding movement and rotation in the elongated slot 56 of a fixture 5S.

Instead of the guide blocl; 28, guide blocks on are provided, one adjacent each radius plate 18 and 19 and on opposite sides of the fixture. Each guide block 6i) is pivoted at its laterally outer end to the fixture for vertical swinging. Compression springs 62 normally urge the blocks to the upper operative position of Figure 8. However, the pivotal connection permits the blocks to swing downwardly into the recesses 64, below the surface of the fixture. As a result, when the fixture is rotated 180 clockwise from the Figure 7 position, the left hand block, which is not in use, may be cammed downwardly by the length of stock 66 being bent engaging the top surface of the block, to clear stock 6o. This construction makes it possible to form a coil S2 by rotating the fixture 180 at one end of the slot and then rotating it 180 following movement to the other end of the slot. Since the guide blocks are carried by the fixture, as distinguished from Figures l-, the added step of returning the guide block to the dotted line position of Figure 3 is omitted.

In Figures 7 and 8 an inner coil of stock is not shown to illustrate that this fixture as well as the one in Figures l-6 may be used where no inner coil is involved. However, it will be understood that the fixture of Figures 7 and 8 can accommodate an inner coil while the outer coil is being bent by reason of the concave inner surfaces of the radius plates.

In both of the forms of the invention shown, it is contemplated that an outer coil may be formed around an inner coil previously formed, and the outer coil is formed in a manner whereby all of the bending taking place at the bottom thereof and the previously formed convolutions are shifted upwardly. As an alternative, the convolutions of the outer coil need not be shifted upwardly but instead succeeding convolutions may be formed on top of those previously formed. Conversely, the inner coil may be placed in the fixture with the unbent length of stock extending from the topmost convolution. Thereafter, the outer coil may be formed by bending it around the radius plates. Here again, two alternatives are possible, that 44is, the bending Mmay all take place at the 4top ofV the coil `with the'previously formed convolutions displaced downwardly along the radius plates by the formation of the latter convolutions or no displacement of the convolutions of the outer coil need take place but each subsequently formed convolution may be formed just beneath the one previously formed.

The drawings andthe `foregoing specification constitute a description of the improved method and device for bending coils in such full, clear, concise and exact terms as Vto enable any person skilled in the art to practice the invention, the scope of which is indicated by the appended claims.

What l claim as my invention is:

l. Apparatus for bending a length of stock compris ing a fixed pin, a fixture having means providing an elongated guide receiving said pin, said fixture being slidable on said pin as `determined by said guide between spaced points along said guide, stock supporting members carried by said fixture Lrespectively adjacent said spaced points, said fixture being rotatable on said pin at said spaced points whereby lthe stock may be coiled upon said directions on said pin to locate the latter at said spaced .points and rotating said fixture on said pin at said spaced points to bend the stock around said members, blocks carried by said fixture at opposite sides of said guide respectively adjacent said members, said blocks being positioned to bear against the outer side of the length of stock being bent between said members, and means to cause said stock to contact said supporting members.

2. Apparatus for bending a length of stock comprising a fixed pivot pin, a fixture having means forming an elongated guide slot receiving said pin, said fixture being slidable on said pin as determined by said slot between opposite ends of said slot, stock supporting members Vcarried by said fixture adjacent opposite ends of said slot, said fixture being rotatable on said pin at opposite ends of said slot whereby the stock may be coiled upon said members by alternately sliding said fixture in opposite directions on said pin to locate the latter at opposite ends of said slot and rotating said fixture on said pin at said opposite ends of said slot to bend the stock around said members, and blocks carried by said fixture at opposite sides of said guide slot respectively adjacent said members, said blocks being positioned to bear against the outer side of the length of stock being bent between said members, resilient means mounting said blocks on said fixture and normally yieldably holding said blocks in operative position, said blocks having cam surfaces engageable with the portion of the stock leading to said fixture for camming said blocks to inoperative position to clear the said portion of stock upon rotation of said fixture, and means to cause said stock to contact said supporting members.

3. Apparatus as defined in claim 2, said stock contacting means including a wiper block engageable with the outer side of the length of stock being bent at the side of the bend opposite said first-mentioned block for resisting outward bending thereof.

4. Apparatus as defined in claim 3 in which said stock supporting members have inner concave stock supporting surfaces facing each other concentric with said pin when the latter is located at the end of said slot adjacent thereto, said inner concave stock supporting surfaces being adapted to support an inner coil of stock in telescoping relation with an outer coil of stock supported by said convex stock supporting surfaces during formation of said outer coil by said bending apparatus.

5. Apparatus for bending a length of stock comprising a fixed pin, a fixture having means providing an elongated guide receiving said pin, said fixture being slidable on said pin as determined by said guide between spaced points along said guide, stock supporting members carried by said fixture respectivelyv adjacent said spaced points, saidfixture Smale being rotatable on said pin at said spaced points whereby the stock may be coiled upon said members by alternately sliding said xture in opposite directions on said pin to locate the latter at said spaced points and rotating said fixture on said pin at said spaced points to bend the stock around said members, blocks movably secured on said fixture at opposite sides of said guide respectively adjacent said members, said blocks normally being positioned to bear against the outer side of the length of stock being bent between said members and being movable from their normal positions to clear the length of stock leading to said xture upon rotation of the latter, and means to cause said stock to contact said supporting members.

References Cited in the file of this patent UNITED STATES PATENTS i Geisenhoner Jan. 15, 1901 Trosiener Aug. 24, 1909 Furnas Jan. 10, 1928 Payne June 28, 1949 FOREIGN PATENTS Great Britain July 21, 1927 

